1. Field of the Invention
The present invention relates to a control method for an inkjet print apparatus and to an inkjet print apparatus, and more particularly to a control method of removing ink from an ink receiving unit for receiving ink that has been preliminary ejected.
2. Description of the Related Art
In an inkjet print apparatus, the place where preliminary ink ejection is performed in order to recover the printing head is usually inside a cap that seals the ejection surface (hereafter, is called the face surface) of the printing head when performing suction-based recovery, or is a specially provided ink receiving unit that has a suction unit. In this place, normally an absorber or the like is provided that holds collected ejected ink.
The amount of ink that is used in one preliminary ejection during the printing operation is a small amount, so in the place where the collected ink is held, the ink accumulates over a comparatively long period of time. The accumulated ink is ejected into a waste ink tank by a suction means, however, during the suction means, if suction is performed when there is not a sufficient level of ink inside the absorber, air is sucked in and ink remains in the place where the collected ink is held. When this remaining accumulated ink is left for a long period of time, the moisture content evaporates, and the ink inside the absorber or suction pump thickens and becomes firmly adhered to the absorber, suction pump and flow path leading to the waste ink tank.
This adhered ink is re-dissolved to a certain extent by preliminary ejection and the suction means, and ejected to the waste ink tank. However, problems may occur such as ink that has adhered by using the ink over a long period of time accumulating and blocking the ink flow path, causing the ink in the portion where the preliminary ejection is performed to overflow, or the accumulated ink on the absorber being transferred to the face surface, causing poor ink ejection or misdirection to occur. Moreover, this accumulated ink is difficult to remove and it may become necessary to disassemble and clean the print apparatus, which in that case requires a lot of work and time.
Technology for suppressing ink from adhering in this way is known in which in addition to preliminary ejection in order to prevent the nozzles from drying out, a separate preliminary ejection is performed in order to re-dissolve the adhering ink, and then the adhering ink is cleaned away by executing a suction means after that (for example, refer to Japanese Patent Laid-Open No. 2002-052744). When performing a preliminary ejection in order to re-dissolve the adhering ink, there is no increase in component parts, so the adhering ink can be effectively removed without the mechanism and control becoming complex.
However, the technology disclosed in Japanese Patent Laid-Open No. 2002-052744 does not estimate to what extent the ink has adhered (accumulated), so it is necessary to reduce the adhering ink by performing this preliminary ejection until the cap become nearly full, and then sucking the ink by the suction means. Therefore, a large amount of ink is used, so wasted ink increases, and the running cost may become high.